Detailed Description

The engine for performing rasterization operations on geometry.

This includes rgb images and depth images. The coordinate system of RenderEngine's viewpoint R is X-right, Y-down and Z-forward with respect to the rendered images.

Output image format

RGB (ImageRgba8U) : the RGB image has four channels in the following order: red, green, blue, and alpha. Each channel is represented by a uint8_t.
Depth (ImageDepth32F) : the depth image has a depth channel represented by a float. For a point in space P, the value stored in the depth channel holds the Z-component of the position vector p_RP. Note that this is different from the range data used by laser range finders (like that provided by DepthSensor) in which the depth value represents the distance from the sensor origin to the object's surface.
Label (ImageLabel16I) : the label image has single channel represented by an int16_t. The value stored in the channel holds a RenderLabel value which corresponds to an object class in the scene or an "empty" pixel (see RenderLabel for more details).

RenderLabels, registering geometry, and derived classes

By convention, when registering a geometry, the provided properties should contain no more than one RenderLabel instance, and that should be the (label, id) property. RenderEngine provides the notion of a default render label that will be applied where no (label, id) RenderLabel property is found. This default value can be one of two values: RenderLabel::kDontCare or RenderLabel::kUnspecified. The choice of default RenderLabel can be made at construction and it affects registration behavior when the (label, id) property is absent:

RenderLabel::kUnspecified: throws an exception.
RenderLabel::kDontCare: the geometry will be included in label images as the generic, non-distinguishing label.

Choosing RenderLabel::kUnspecified is best in a system that wants explicit feedback and strict enforcement on a policy of strict label enforcement – everything should receive a meaningful label. The choice of RenderLabel::kDontCare is best for a less strict system in which only some subset of geometry need be explicitly specified.

Derived classes configure their de facto default RenderLabel value, or a user-configured default value, at construction, subject to the requirements outlined above.

Derived classes should not access the (label, id) property directly. RenderEngine provides a method to safely extract a RenderLabel value from the PerceptionProperties, taking into account the configured default value and the documented RenderLabel semantics; see GetRenderLabelOrThrow().

#include <drake/geometry/render/render_engine.h>

Public Member Functions
	RenderEngine (const RenderLabel &default_label=RenderLabel::kUnspecified)
	Constructs a RenderEngine with the given default render label. More...

virtual	~RenderEngine ()=default

std::unique_ptr< RenderEngine >	Clone () const
	Clones the render engine – making the RenderEngine compatible with copyable_unique_ptr. More...

bool	RegisterVisual (GeometryId id, const Shape &shape, const PerceptionProperties &properties, const math::RigidTransformd &X_WG, bool needs_updates=true)
	Requests registration of the given shape with this render engine. More...

bool	RemoveGeometry (GeometryId id)
	Removes the geometry indicated by the given `id` from the engine. More...

bool	has_geometry (GeometryId id) const
	Reports true if a geometry with the given `id` has been registered with `this` engine. More...

template<typename T >
void	UpdatePoses (const std::unordered_map< GeometryId, math::RigidTransform< T >> &X_WGs)
	Updates the poses of all geometries marked as "needing update" (see RegisterVisual()). More...

virtual void	UpdateViewpoint (const math::RigidTransformd &X_WR)=0
	Updates the renderer's viewpoint with given pose X_WR. More...

RenderLabel	default_render_label () const
	Reports the render label value this render engine has been configured to use. More...

Rendering using fully-specified camera models
These methods allow for full specification of the camera model – its intrinsics and render engine parameters. See the documentation of ColorRenderCamera and DepthRenderCamera for the full details.
void	RenderColorImage (const ColorRenderCamera &camera, systems::sensors::ImageRgba8U *color_image_out) const
	Renders the registered geometry into the given color (rgb) image based on a fully specified camera. More...

void	RenderDepthImage (const DepthRenderCamera &camera, systems::sensors::ImageDepth32F *depth_image_out) const
	Renders the registered geometry into the given depth image based on a fully specified camera. More...

void	RenderLabelImage (const ColorRenderCamera &camera, systems::sensors::ImageLabel16I *label_image_out) const
	Renders the registered geometry into the given label image based on a fully specified camera. More...

Public Member Functions inherited from ShapeReifier
virtual	~ShapeReifier ()=default

virtual void	ImplementGeometry (const Sphere &sphere, void *user_data)

virtual void	ImplementGeometry (const Cylinder &cylinder, void *user_data)

virtual void	ImplementGeometry (const HalfSpace &half_space, void *user_data)

virtual void	ImplementGeometry (const Box &box, void *user_data)

virtual void	ImplementGeometry (const Capsule &capsule, void *user_data)

virtual void	ImplementGeometry (const Ellipsoid &ellipsoid, void *user_data)

virtual void	ImplementGeometry (const Mesh &mesh, void *user_data)

virtual void	ImplementGeometry (const Convex &convex, void *user_data)

virtual void	ImplementGeometry (const MeshcatCone &cone, void *user_data)

Protected Member Functions
virtual bool	DoRegisterVisual (GeometryId id, const Shape &shape, const PerceptionProperties &properties, const math::RigidTransformd &X_WG)=0
	The NVI-function for sub-classes to implement actual geometry registration. More...

virtual void	DoUpdateVisualPose (GeometryId id, const math::RigidTransformd &X_WG)=0
	The NVI-function for updating the pose of a render geometry (identified by `id`) to the given pose X_WG. More...

virtual bool	DoRemoveGeometry (GeometryId id)=0
	The NVI-function for removing the geometry with the given `id`. More...

virtual std::unique_ptr< RenderEngine >	DoClone () const =0
	The NVI-function for cloning this render engine. More...

virtual void	DoRenderColorImage (const ColorRenderCamera &camera, systems::sensors::ImageRgba8U *color_image_out) const
	The NVI-function for rendering color with a fully-specified camera. More...

virtual void	DoRenderDepthImage (const DepthRenderCamera &camera, systems::sensors::ImageDepth32F *depth_image_out) const
	The NVI-function for rendering depth with a fully-specified camera. More...

virtual void	DoRenderLabelImage (const ColorRenderCamera &camera, systems::sensors::ImageLabel16I *label_image_out) const
	The NVI-function for rendering label with a fully-specified camera. More...

RenderLabel	GetRenderLabelOrThrow (const PerceptionProperties &properties) const
	Extracts the `(label, id)` RenderLabel property from the given `properties` and validates it (or the configured default if no such property is defined). More...

virtual void	SetDefaultLightPosition (const Vector3< double > &X_DL)
	Provides access to the light for manual configuration since it's currently bound to the camera position. More...

Implements CopyConstructible, CopyAssignable, MoveConstructible, MoveAssignable
	RenderEngine (const RenderEngine &)=default

RenderEngine &	operator= (const RenderEngine &)=default

	RenderEngine (RenderEngine &&)=default

RenderEngine &	operator= (RenderEngine &&)=default

Protected Member Functions inherited from ShapeReifier
	ShapeReifier ()=default

virtual void	ThrowUnsupportedGeometry (const std::string &shape_name)
	Derived ShapeReifiers can replace the default message for unsupported geometries by overriding this method. More...

	ShapeReifier (const ShapeReifier &)=default

ShapeReifier &	operator= (const ShapeReifier &)=default

	ShapeReifier (ShapeReifier &&)=default

ShapeReifier &	operator= (ShapeReifier &&)=default

Static Protected Member Functions
template<typename ImageType >
static void	ThrowIfInvalid (const systems::sensors::CameraInfo &intrinsics, const ImageType image, const char image_type)

RenderLabel-Color Utilities
Some rasterization pipelines don't support channels of RenderLabel::ValueType; typically, they operate in RGB color space. The following utilities support those pipelines by providing conversions between labels and colors. The mapping does not produce colors that are useful to humans – two labels with "near by" values will produces colors that most humans cannot distinguish, but the computer can. Do not use these utilities to produce the prototypical "colored label" images. The label-to-color conversion can produce one of two different color encodings. These encodings are not exhaustive but they are typical of the encodings that have proven useful. The supported color encodings consist of three RGB channels where each channel is either byte-valued in that they are encoded with unsigned bytes in the range [0, 255] per channel or double-valued such that each channel is encoded with a double in the range [0, 1]. Conversion to RenderLabel is only supported from byte-valued color values.
static RenderLabel	LabelFromColor (const systems::sensors::ColorI &color)
	Transforms the given byte-valued RGB color value into its corresponding RenderLabel. More...

static systems::sensors::ColorI	GetColorIFromLabel (const RenderLabel &label)
	Transforms `this` render label into a byte-valued RGB color. More...

static systems::sensors::ColorD	GetColorDFromLabel (const RenderLabel &label)
	Transforms `this` render label into a double-valued RGB color. More...

Friends
class	RenderEngineTester

Constructor & Destructor Documentation

◆ RenderEngine() [1/3]

RenderEngine ( const RenderLabel & default_label = RenderLabel::kUnspecified )

explicit

Constructs a RenderEngine with the given default render label.

The default render label is applied to geometries that have not otherwise specified a (label, id) property. The value must be either RenderLabel::kUnspecified or RenderLabel::kDontCare. (See this section for more details.)

Exceptions

std::exception if the default render label is not one of the two allowed labels.

◆ ~RenderEngine()

virtual ~RenderEngine ( )

virtualdefault

◆ RenderEngine() [2/3]

RenderEngine ( const RenderEngine & )

protecteddefault

◆ RenderEngine() [3/3]

RenderEngine ( RenderEngine && )

protecteddefault

Member Function Documentation

◆ Clone()

std::unique_ptr<RenderEngine> Clone ( ) const

Clones the render engine – making the RenderEngine compatible with copyable_unique_ptr.

◆ default_render_label()

RenderLabel default_render_label ( ) const

Reports the render label value this render engine has been configured to use.

◆ DoClone()

virtual std::unique_ptr<RenderEngine> DoClone ( ) const

protectedpure virtual

The NVI-function for cloning this render engine.

◆ DoRegisterVisual()

virtual bool DoRegisterVisual	(	GeometryId	id,
		const Shape &	shape,
		const PerceptionProperties &	properties,
		const math::RigidTransformd &	X_WG
	)

protectedpure virtual

The NVI-function for sub-classes to implement actual geometry registration.

If the derived class chooses not to register this particular shape, it should return false.

A derived render engine can choose not to register geometry because, e.g., it doesn't have default properties. This is the primary mechanism which enables different renderers to use different geometries for the same frame. For example, a low-fidelity renderer may use simple geometry whereas a high-fidelity renderer would require a very detailed geometry. Both geometries would have PerceptionProperties, but, based on the provided property groups and values, one would be accepted and registered with one render engine implementation and the other geometry with another render engine.

In accessing the RenderLabel property in properties derived class should exclusively use GetRenderLabelOrThrow().

◆ DoRemoveGeometry()

virtual bool DoRemoveGeometry ( GeometryId id )

protectedpure virtual

The NVI-function for removing the geometry with the given id.

Parameters

id	The id of the geometry to remove.

Returns: True if the geometry was registered with this RenderEngine and removed, false if it wasn't registered in the first place.

◆ DoRenderColorImage()

virtual void DoRenderColorImage	(	const ColorRenderCamera &	camera,
		systems::sensors::ImageRgba8U *	color_image_out
	)		const

protectedvirtual

The NVI-function for rendering color with a fully-specified camera.

When RenderColorImage calls this, it has already confirmed that color_image_out is not nullptr and its size is consistent with the camera intrinsics.

Exceptions

std::exception in its default implementaiton indicating that it has not been implemented. Derived RenderEngine classes must implement this to support rendering color images.

◆ DoRenderDepthImage()

virtual void DoRenderDepthImage	(	const DepthRenderCamera &	camera,
		systems::sensors::ImageDepth32F *	depth_image_out
	)		const

protectedvirtual

The NVI-function for rendering depth with a fully-specified camera.

When RenderDepthImage calls this, it has already confirmed that depth_image_out is not nullptr and its size is consistent with the camera intrinsics.

Exceptions

std::exception in its default implementaiton indicating that it has not been implemented. Derived RenderEngine classes must implement this to support rendering depth images.

◆ DoRenderLabelImage()

virtual void DoRenderLabelImage	(	const ColorRenderCamera &	camera,
		systems::sensors::ImageLabel16I *	label_image_out
	)		const

protectedvirtual

The NVI-function for rendering label with a fully-specified camera.

When RenderLabelImage calls this, it has already confirmed that label_image_out is not nullptr and its size is consistent with the camera intrinsics.

Exceptions

std::exception in its default implementaiton indicating that it has not been implemented. Derived RenderEngine classes must implement this to support rendering label images.

◆ DoUpdateVisualPose()

virtual void DoUpdateVisualPose	(	GeometryId	id,
		const math::RigidTransformd &	X_WG
	)

protectedpure virtual

The NVI-function for updating the pose of a render geometry (identified by id) to the given pose X_WG.

Parameters

id	The id of the render geometry whose pose is being set.
X_WG	The pose of the render geometry in the world frame.

◆ GetColorDFromLabel()

static systems::sensors::ColorD GetColorDFromLabel ( const RenderLabel & label )

staticprotected

Transforms this render label into a double-valued RGB color.

◆ GetColorIFromLabel()

static systems::sensors::ColorI GetColorIFromLabel ( const RenderLabel & label )

staticprotected

Transforms this render label into a byte-valued RGB color.

◆ GetRenderLabelOrThrow()

RenderLabel GetRenderLabelOrThrow ( const PerceptionProperties & properties ) const

protected

Extracts the (label, id) RenderLabel property from the given properties and validates it (or the configured default if no such property is defined).

Exceptions

std::exception If the tested render label value is deemed invalid.

◆ has_geometry()

bool has_geometry ( GeometryId id ) const

Reports true if a geometry with the given id has been registered with this engine.

◆ LabelFromColor()

static RenderLabel LabelFromColor ( const systems::sensors::ColorI & color )

staticprotected

Transforms the given byte-valued RGB color value into its corresponding RenderLabel.

◆ operator=() [1/2]

RenderEngine& operator= ( RenderEngine && )

protecteddefault

◆ operator=() [2/2]

RenderEngine& operator= ( const RenderEngine & )

protecteddefault

◆ RegisterVisual()

bool RegisterVisual	(	GeometryId	id,
		const Shape &	shape,
		const PerceptionProperties &	properties,
		const math::RigidTransformd &	X_WG,
		bool	needs_updates = `true`
	)

Requests registration of the given shape with this render engine.

The geometry is uniquely identified by the given id. The renderer is allowed to examine the given properties and choose to not register the geometry.

Typically, derived classes will attempt to validate the RenderLabel value stored in the (label, id) property (or its configured default value if no such property exists). In that case, attempting to assign RenderLabel::kEmpty or RenderLabel::kUnspecified will cause an exception to be thrown (as documented).

Parameters

id	The geometry id of the shape to register.
shape	The shape specification to add to the render engine.
properties	The perception properties provided for this geometry.
X_WG	The pose of the geometry relative to the world frame W.
needs_updates	If true, the geometry's pose will be updated via UpdatePoses().

Returns: True if the RenderEngine implementation accepted the shape for registration.

Exceptions

std::exception if the shape is an unsupported type, the shape's RenderLabel value is RenderLabel::kUnspecified or RenderLabel::kEmpty, or a geometry has already been registered with the given id.

◆ RemoveGeometry()

bool RemoveGeometry ( GeometryId id )

Removes the geometry indicated by the given id from the engine.

Parameters

id	The id of the geometry to remove.

Returns: True if the geometry was removed (false implies that this id wasn't registered with this engine).

◆ RenderColorImage()

void RenderColorImage	(	const ColorRenderCamera &	camera,
		systems::sensors::ImageRgba8U *	color_image_out
	)		const

Renders the registered geometry into the given color (rgb) image based on a fully specified camera.

Parameters

	camera	The render engine camera properties.
[out]	color_image_out	The rendered color image.

Exceptions

std::exception if color_image_out is nullptr or the size of the given input image doesn't match the size declared in camera.

◆ RenderDepthImage()

void RenderDepthImage	(	const DepthRenderCamera &	camera,
		systems::sensors::ImageDepth32F *	depth_image_out
	)		const

Renders the registered geometry into the given depth image based on a fully specified camera.

In contrast to the other rendering operations, depth images don't have an option to display the window; generally, basic depth images are not readily communicative to humans.

Parameters

	camera	The render engine camera properties.
[out]	depth_image_out	The rendered depth image.

Exceptions

std::exception if depth_image_out is nullptr or the size of the given input image doesn't match the size declared in camera.

◆ RenderLabelImage()

void RenderLabelImage	(	const ColorRenderCamera &	camera,
		systems::sensors::ImageLabel16I *	label_image_out
	)		const

Renders the registered geometry into the given label image based on a fully specified camera.

Note: This uses the ColorRenderCamera as label images are typically rendered to be exactly registered with a corresponding color image.

Parameters

	camera	The render engine camera properties.
[out]	label_image_out	The rendered label image.

Exceptions

std::exception if label_image_out is nullptr or the size of the given input image doesn't match the size declared in camera.

◆ SetDefaultLightPosition()

virtual void SetDefaultLightPosition ( const Vector3< double > & X_DL )

protectedvirtual

Provides access to the light for manual configuration since it's currently bound to the camera position.

This is a temporary measure to facilitate benchmarking and create visible shadows, and should not be used publicly.

Parameters

X_DL	The pose of the light in a frame D that is attached to the camera position. In this frame D, the camera is located at (0, 0, 1), looking towards (0, 0, 0) at a distance of 1, with up being (0, 1, 0).

◆ ThrowIfInvalid()

static void ThrowIfInvalid	(	const systems::sensors::CameraInfo &	intrinsics,
		const ImageType *	image,
		const char *	image_type
	)

staticprotected

◆ UpdatePoses()

void UpdatePoses ( const std::unordered_map< GeometryId, math::RigidTransform< T >> & X_WGs )

Updates the poses of all geometries marked as "needing update" (see RegisterVisual()).

Parameters

X_WGs The poses of all geometries in SceneGraph (measured and expressed in the world frame). The pose for a geometry is accessed by that geometry's id.

◆ UpdateViewpoint()

virtual void UpdateViewpoint ( const math::RigidTransformd & X_WR )

pure virtual

Updates the renderer's viewpoint with given pose X_WR.

Parameters

X_WR	The pose of renderer's viewpoint in the world coordinate system.

Implemented in RenderEngineVtk, and RenderEngineGl.

Friends And Related Function Documentation

◆ RenderEngineTester

friend class RenderEngineTester

friend

The documentation for this class was generated from the following file:

drake/geometry/render/render_engine.h

Detailed Description

Output image format

RenderLabels, registering geometry, and derived classes

Public Member Functions

Protected Member Functions

Static Protected Member Functions

Friends

Constructor & Destructor Documentation

◆ RenderEngine() [1/3]

◆ ~RenderEngine()

◆ RenderEngine() [2/3]

◆ RenderEngine() [3/3]

Member Function Documentation

◆ Clone()

◆ default_render_label()

◆ DoClone()

◆ DoRegisterVisual()

◆ DoRemoveGeometry()

◆ DoRenderColorImage()

◆ DoRenderDepthImage()

◆ DoRenderLabelImage()

◆ DoUpdateVisualPose()

◆ GetColorDFromLabel()

◆ GetColorIFromLabel()

◆ GetRenderLabelOrThrow()

◆ has_geometry()

◆ LabelFromColor()

◆ operator=() [1/2]

◆ operator=() [2/2]

◆ RegisterVisual()

◆ RemoveGeometry()

◆ RenderColorImage()

◆ RenderDepthImage()

◆ RenderLabelImage()

◆ SetDefaultLightPosition()

◆ ThrowIfInvalid()

◆ UpdatePoses()

◆ UpdateViewpoint()

Friends And Related Function Documentation

◆ RenderEngineTester